title: Doses and models in risk assessment analysis for bronchial hyperresponsiveness.
abstract: The aims of this study are: (1) to evaluate whether the estimates of the association of risk factors with bronchial hyperresponsiveness (BHR) depends on the accumulated dose administered in challenge tests; and (2) to verify whether a model developed for survival studies (Weibull regression) is suited to analyze methacholine dose-response curves. For these purposes, 863 challenge tests, from EC Respiratory Health Survey in Italy, up to a cumulative dose of 6 mg methacholine, were analyzed by Weibull regression and by traditional methods (logistic model and linear model), both before and after truncation of the curves at 2 mg. With all methods the main risk factors for BHR were respiratory symptoms and atopy while age and airway caliber exerted a protective action. Our results confirmed that in epidemiological surveys 2 mg methacholine is enough to fully appreciate the effect of risk factors on BHR and showed that the Weibull model explains the observed variability better than linear and logistic regressions.
authors.affiliation: Cattedra di Statistica Medica e Biometria, Università di Verona, Italy.
authors.forename: R
authors.initials: R
authors.lastname: de Marco
authors.forename: M
authors.initials: M
authors.lastname: Bugiani
authors.forename: E
authors.initials: E
authors.lastname: Zanolin
authors.forename: G
authors.initials: G
authors.lastname: Verlato
authors.forename: B
authors.initials: B
authors.lastname: Rijcken
mesh_terms: D000328:Adult; D016535:Bronchial Hyperreactivity / Q000175:diagnosis*; D001985:Bronchial Provocation Tests / Q000592:standards*; D016085:Bronchoconstrictor Agents / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D016210:Methacholine Chloride / Q000008:administration & dosage; D015233:Models, Statistical; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis
chemical_list: D016085:Bronchoconstrictor Agents; D016210:Methacholine Chloride